Circ pump automation help

rbphhc

Hi all - I have a boiler/ indirect setup for DHW and in-floor heat, and trying to automate indirect circ through the boiler.

Is there any way to trigger indirect circulation *whenever* multiple things happen? I notice better performance if the tank circulates whenever recirc pump runs, whenever DHW is used, whenever hydronic circ runs, all of which run down the indirect tank temp.

This gives the indirect a 'head start,' rather than waiting for the low limit to hit.

But I can't think or any simple way to wire this. If multiple t-stats trigger the same relay, then it will also function in reverse - i.e. the recirc trigger will set off the hydronic pump, etc.

Thoughts? If not, I'll just do it the normal way. Thanks.

Jamie Hall

Not hard. But you will need one relay for each item you want to control your indirect circulation. Wire the coil of a relay representing the recirc pump, for insannce, to that pump, and the normally closed contacts of the relay to the indirect pump. And one for the hydronic circ. And one for whatever else -- you'll need a flow switch for when the DHW is used. All those contacts in parallel.

rbphhc

Jamie Hall said:

Not hard. But you will need one relay for each item you want to control your indirect circulation. Wire the coil of a relay representing the recirc pump, for insannce, to that pump, and the normally closed contacts of the relay to the indirect pump. And one for the hydronic circ. And one for whatever else -- you'll need a flow switch for when the DHW is used. All those contacts in parallel.

Excellent, thank you. I'm gonna have to draw that out, wiring not my strong suit. Will get back if any questions. Thx again!

ratio

You could use a current switch (e.g. https://www.functionaldevices.com/product/ribxgf/) to monitor any other pumps that you want to start your indirect pump. Easier (& possibly safer) than adding a relay to a line voltage circuit. Note that the model linked above isn't capable of switching a line-voltage load by itself.